1. Field of Invention
The present invention pertains to the field of pet doors. More particularly, this invention is related to a pet door having a lock mechanism provided for selected ingress and egress therethrough, the pet door being provided with an alarm-actuated mechanism for automatically disengaging the lock mechanism to allow the safe egress of any animal in the associated structure.
2. Description of the Related Art
In the field of pet care, it is well known that pets face the same dangers as humans when in emergency situations such as house fires. Often, when pets are lost in fires, the loss to the owners is like that of the loss of a family member. It is further well known that many pet doors have locking mechanisms for selectively controlling the ingress and egress of animals into and out of the associated structure. Representative pet doors include electronic devices that control the allowable times and direction of passage through the pet door, as well as the allowed animals which may pass therethrough.
Typical of the art are those devices disclosed in the following U.S. Patents:
U.S. Pat. No.Inventor(s)Issue Date4,022,263R. W. Beckett et al.May 10, 19774,036,178B. T. Lee et al.Jul. 19, 19774,497,133P. T. BlenkinsopFeb. 5, 19855,570,655A. TargaNov. 5, 19965,992,096P. De La Cerda et al.Nov. 30, 19996,297,739D. K. SmallOct. 2, 20016,560,926M. E. GillettMay 13, 2003
Of these patents, Beckett et al., disclose, in their '263 patent, a magnetically actuated cat door wherein the a cat can wears a magnet which allows free ingress and egress through a pet door while other cats are effectively barred from entering.
Lee et al. ('178), disclose an electronic lock and key system for allowing access into and out of a structure by a selected animal and preventing access by all other animals. A passive key provides selective access without having a self contained power source. In this passive transponder arrangement, a passive electronic key processes induced or radiated electronic signals to generate a transponder signal for controlling access.
In his '133 patent, Blenkinsop discloses a control circuit for unlatching a pet door, the control circuit including a transmitter coil, a pulse driver for pulse energizing the coil, and a discriminator for detecting a.c. components in the coil current caused by currents induced in an outside tuned circuit brought adjacent the coil, e.g. around the neck of a pet seeking entry, and for comparing the frequency of the a.c. components with a standard. A latch drive circuit responds to the discriminator for operating the door latch if the frequency comparison is satisfactory.
Targa, in his '655 patent, discloses a device for deterring animal access to a location. The '655 device includes a generator for generating a field and a sensor for sensing the presence of the field near the location. One of the generator and the sensor is removably secured on an animal. A deterrent output signal unit is responsive to the sensor for generating an output signal in the presence of the field, the output signal being of sufficient magnitude to deter the animal from the location.
The '096 patent issued to De La Cerda et al., discloses a controllable animal access system connectable to the door of a building which has an opening covered by a pivotally moveable animal door. The animal access system of the '096 patent has a motion detector associated with a reader which detects an encoded pet tag worn by a selected animal and actuates locking and unlocking mechanisms in response to reading an accepted code.
Small ('739) discloses a system and method for providing access to a secured enclosure, such as a house or a fenced yard, to only a set of one or more selected animals. Each selected animal carries an identification device with an identifying code. An identification sensor scans for a selected identification device upon the detection of an animal's existence near the animal door. For detecting an animal at the outside of the animal door, a weight sensor is used, and for detecting an animal at the inside of the animal door, a motion sensor is used. The weight sensor is also configured to discriminate between the weight of each of the selected animals from unauthorized animals.
Gillett, in the '926 patent, teaches a pet door unit having a housing, an opening mechanism, a pet door, a receiver and a portable transmitter. The opening mechanism includes a motor having a screw drive and a carriage connected to the top of the pet door. The carriage moves along the length of a screw shaft of the screw drive as the shaft rotates to open and close the door. A detector is mounted on each of the sidewalls of the housing to detect an object in the opening of the housing and prevent the door from closing when an object is detected in the opening. To open the door, a user presses a button on the portable transmitter which sends a signal to the receiver which activates the opening mechanism to move the door to the open position.
In order to assist the pet in leaving a dwelling, several devices have been provided for opening an enclosure such as a cage, a pen or a house in which the animal is housed, thus permitting the exit of the pet from the enclosure. Such devices typically respond to the detection of fire or smoke. However, should the devices fail to function to open an exit for the pet from the enclosure, no provision is made for a pet owner, a firefighter, or other rescue worker to locate the pet and remove the pet from danger.
Typical of the art are those devices disclosed in the following U.S. Patents:
U.S. Pat. No.Inventor(s)Issue Date507,322A. R. HolmesOct. 24, 1893520,395J. S. EdmondsMay 22, 18941,006,914C. S. CoxOct. 24, 19111,310,612E. EskelinJul. 22, 19194,837,560C. L. NewberryJun. 6, 19895,642,092G. Dunne et al.Jun. 24, 19975,651,331C. J. Cleri, Jr.Jul. 29, 19975,652,563A. B. MausJul. 29, 19976,318,296T. T. NguyenNov. 20, 20016,710,714M. ConwayMar. 23, 2004
Holmes, in his '322 patent, teaches an electric alarm system for use in horse stables. The alarm system is adapted to alert a remote location of a fire in the stable, and will automatically releases the horses housed in the stable in the event a fire is detected. Edmonds, in his '395 patent, as well as Cox in his '914 patent, disclose similar alarm and release systems using mechanical levers and cables. Eskelin ('612) provides yet another system for releasing livestock, the system using a flexible connector that is burnable or capable of being melted. When a fire burns the connector, weights at one end of the connector fall and engage the end of a sliding rod. The rod is connected to the locking devices on the stall gates such that when the rod is so engaged, the rod is slid and the locking devices are unlocked, thereby releasing the livestock.
Newberry, in his '560 patent, discloses an apparatus for automatically unlocking the guard bars on a window in response to the output signal of a fire detection device. A smoke alarm includes a pair of relay-controlled contacts used in conjunction with a solenoid arrangement to unlock the window bars. Power to the smoke detector and the solenoid circuit is supplied by a rechargeable battery.
The '092 patent issued to Dunne et al., teaches an automatic evacuation assistance system for assisting animals or people in existing a structure. The '092 device includes an event detector, such as a smoke detector for providing an event detection signal. The event detection signal is received by an exit control device which is coupled to an exit opening, for allowing the exit opening to open, providing an exit path to the outside of a structure. A transmitter transmits an alert in the form of a sound, smell, or visual signal to attract the person or animals to the exit path and exit opening.
Cleri, Jr., in his '331 patent, teaches an escape device for pets including a passageway opening from the inside to the outside of the enclosure. The passageway is normally closed by a primary door. An apparatus is provided for opening the door at the onset of a smoke emitting emergency such as a fire such that the door is open for safe egress for the pet or pets. Cleri further provides for a pre-recorded message preferably in the owner's voice directing and/or commanding the pet or pets to the open passageway.
The '563 patent issued to Maus discloses a safety system for a stable. The '563 device includes “smart detectors” installed in the stable for detecting at least one abnormal condition in the stable, a siren and/or flashing strobe installed in each stall for spooking horses out of their stalls, an electromagnetic lock provided on each said door, a power source supplying power to each said electro-magnetic lock keeping each door closed in the absence of the abnormal condition, and a controlling means continually monitoring the “smart detectors.” Once the abnormal condition has been detected, the controlling unit immediately turns down the power supplied to each electromagnetic lock and, with a certain delay, actuates the siren and/or flashing strobe.
Nguyen, in the '296 patent, teaches an animal holding facility with an automatic evacuation system. An automatic fire, smoke and/or carbon dioxide detection system utilizing a plurality of smoke, fire and/or carbon monoxide sensors is disclosed by Nguyen. An audible alarm activates upon triggering of the sensors. A common fire door opens automatically and a hydraulic animal ejection means gently sweeps or guides the animal out of the kennel through the fire exits.
Conway discloses a system and method for freeing a pet from a portable holding cage in his '714 patent. The portable holding cage is provided with a door that can be locked in a closed position by an electromechanical lock. The operation of the lock is controlled by a systems controller which monitors alarm signals transmitted to it from a remote smoke detector. The transmitted alarm signals can be audible alarm signals, radio alarm signals or optical alarm signals. Once the alarm signal is received and identified by the systems controller, the systems controller activates the lock and opens the door to the holding cage.